docs: Add compat-only hooks, useDebugValue, and expound upon useLayoutEffect
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rschristian
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Jul 14, 2025
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| apply: 'build', | ||
| async buildStart() { |
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I mentioned this in the other PR but looks like it was missed: this.emitFile cannot be used in Vite's dev mode and it'll emit warnings over this. The closest equivalent for us would be adding a middleware likely, as nothing else consumes the result, but in lieu of that, we should limit this to builds.
rschristian
commented
Jul 14, 2025
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| Optionally, you can also pass a function as the second argument to `useDebugValue` for use as the "formatter". | ||
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| ```jsx | ||
| import { useDebugValue, useState } from 'preact/hooks'; | ||
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| function useCount() { | ||
| const [count, setCount] = useState(0); | ||
| useDebugValue(count, c => `Count: ${c}`); | ||
| return [count, setCount]; | ||
| } | ||
| ``` |
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Side note: the formatter arg is lazy in React, hence why it exists, but our impl is very much not. It immediately calls the formatter upon ever render of the component, regardless of whether devtools are inspecting the element.
Not sure if that was intentional or not.
JoviDeCroock
approved these changes
Jul 15, 2025
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We're missing a number of compat-only hooks from our docs and per our Algolia stats, a number of user are searching for them. As such, I felt it was worth adding docs even for the hooks that are stubbed out.
While I was at it I noticed we were missing docs for
useDebugValueand ouruseLayoutEffectdescription was quite light, so I added them too.